IR spectra of catalysts and adsorbed molecules

Comparative Studies of Phosphate-Modified CeO2 and Al2O3 for Mechanistic Understanding of Dichloromethane Oxidation and Chloromethane Formation

“…Moreover, a series of C–H/D vibration bands assigned to H-CO x or D-CO x species (such as CH 3 O/CD 3 O, −CHO/–CDO, or HCOOH/DCOOD) were detected at 2700–3000 cm –1 (DCM) or 2000–2200 cm –1 (DDCM), and the detail assignments are listed in Table . It should be noted that, the bands at 2170–2205 cm –1 belonged to the C–D stretching vibrations of formate, and the corresponding C–H stretching vibrations should be in the interval 2860–2910 cm –1 , which shifted from about 2170 to 2197 cm –1 with the increase of the temperature; this blue shift was also reported in the adsorption of DCOOD on the surface of catalysts . Moreover, the predominant formate species including bidentate formate were also further confirmed by the appearance of a series of C–O vibration bands, and the intensity of these bands increased first and then decreased with the rise of the reaction temperature.…”

“…It should be noted that, the bands at 2170−2205 cm −1 belonged to the C−D stretching vibrations of formate, and the corresponding C−H stretching vibrations should be in the interval 2860−2910 cm −1 , which shifted from about 2170 to 2197 cm −1 with the increase of the temperature; this blue shift was also reported in the adsorption of DCOOD on the surface of catalysts. 46 Moreover, the predominant formate species including bidentate formate were also further confirmed by the appearance of a series of C−O vibration bands, and the intensity of these bands increased first and then decreased with the rise of the reaction temperature. The strongest peak was observed at 150 °C over CeO 2 -based catalysts.…”